Extension-ladder.



No. 637,082. Patented Nov. l4, I899.

F. 0. CARLSON.

EXTENSION LADDER.

(Application filed Mar. 2, 1897.)

(No Model.)

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m: "cams PETERS co. FHOTULITHD, WASHINGTON. n cy UNITED STATES -FRANS 0. OARLSON, on onIoAeo, ILLINoIs EXTENSlON- LAD DER L srn'cnrrcAcrioiv forming part'of Letters Patent No. 637,082, dated November 14, 1895.

Application filed Math 2 1897.

T0 till whom it may concern.-

Be it known that I, FRANS O. GARLSON, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Extension-Ladders, which are fully set forth in the following specification, reference being had to the accompanying drawings, forming a part hereof, and in which- Figure 1 shows my said improved ladder in front view, partly extended. Fig. 2 shows a vertical section on the plane 2 2 of Fig. 1.

Like letters refer to like parts.

The object of my invention is to produce an extension-ladderin three or more sections, whereby great heights may be reached with a a number of superimposed sections, which may thus be more conveniently handled, stored, and used than is the case with longer sections. To attain said desirable ends,I construct my said new ladder in substantially the following manner, namely: I make a base or ground section a, and within the side bars and on the rounds of which I connect a section b, and within it, in like manner, a section 0, and To the inner sides and upper end of the section a are attached hooks or rightangled plates g, which reach over the top edge of the section b, and thereby holdit to section a. To the section b are attached like formed and placed hooks h, which hold section c. Said hooks hold the series of sections together and allow them to slide over each other. Pins or stops 'i and j in the lower ends of b and c strike against the edges of the hooks g and h to prevent further motion of their respective sections. To the inner sides of the side rails of the sections 0 and d are attached pendulum braces or swinging arms and Z, which swing on pivots r. Said arms are each expanded in the plane of the arms, so as to embrace between their fingers Z the opposed rounds of the adjoining sections. Byinclining the ladders from the perpendicular in one direction the free end of the arm will be caused to move into its own section from its neighbor, and by an opposite inclination the end of the arm will pass into the adjacent section and cause its finger to pass over the round of its sec- Serial No. 625,740. (No model.)

tion, thus placing it in such a position that the section will'be held in place, and thus lock the parts thereat. To unlock the parts,tlie up per section has to be moved upward beyond the length of the finger and then the arm brought forward, so that the rear finger shall be in front of the round of the lower section. This is done most simply by inclining the ladder in the opposite direction far enough to cause the arm or arms to assume said position by gravity. Then the upper or outer section will slide down to the ground freely. This is true of section 2) relative to section a and of section 0 relative to section b. To operate said parts byacord or rope, an arrangement far more convenient than without such device, I attach the cord to the lower round f of the upper or outer section 0 and pass it under its rounds as cord 'm over the top round e of section b, then bring it down as cord at behind the rounds of section b and pass it under the lower round (1 of section a, thence up as cord 0 on the under or rear side of the rounds of section a, then over the top round (1 of section a and down in front of the rounds of section a as cord 19 to the lower round e of section b, and thence up as cord q to the round f, from which the cord was started, both ends being fastened to the same round, thus forming an endless cord through which said several sections are operatively connected and wherewith the said ladder is now fully completed. To extend saidsections into a long ladder, pull the cord 0 downward. This will pull the parts 10 q upward and with them raise both sections 19 and 0. Then reach across to the cord n and pull downward on it. This will shorten the end m, and thus raise the section 0, the cords p q following as cord n passes down and under the rounds d to supply the rising cord 0, which in turn supplies the descending cord 19, which in turn supplies the rising cord (1, and conversely for each when the ladder is shortened.

Pulleys sor 8 may be attached to the rounds to be used in place of the rounds when desired. The principle of the structure is not altered thereby, as is obvious.

What I claim is- The combination with a series of superimposed ladder-sections and mechanism to hold sliding sections adapted to span opposed them together, of an endless operating-cord rounds of adjacent sections, substantially as fixedly held 'by the lower round of the top specified.

ladder-section and formed into loop-sections FRANS O. CARLSON. 5 m, n, 0, p, q, having sliding, or moving 100p Witnesses:

ends around (I, d, e and e, and pivoted grav- WM. ZIMMERMAN,

ity-actuated hanging bifingered arms on said THOMAS D. HAWLEY. 

